APPEARANCE: Himamushi nyūdō is a grotesque yōkai which lives under floorboards and crawls out at night time. It vaguely resembles a Buddhist monk, but it has a long neck, sharp claws, a body covered in thick, dark hair, and a very long tongue which it uses to lap up the oil from lamps.

INTERACTIONS: Himamushi nyūdō bothers people who are working hard or studying late at night by jumping out of the darkness and scaring them. Although it doesn’t directly attack people, its presence is disturbing enough. It blows out the lights suddenly, and it licks up the precious lamp oil, making it difficult to continue working.

ORIGIN: According to Toriyama Sekien’s description of this yōkai in Konjaku hyakki shūi, himamushi nyūdō is born from those who were lazy in life, carelessly wasting time from birth to death.

The word “oven bug” in its name is probably a reference to cockroaches. The hima kanji in this yokai’s name can also be read kama—and likely refers to the kamado, a traditional Japanese oven. Cockroaches have quite a few nicknames in Japanese; among them himushi (“fire bug”) and hitorimushi (“lamp bug”), both of which sound similar to himamushi. Cockroaches and other pests would have fed on the fish oil in Edo period oil lamps; just like this yōkai. Cockroaches live in dark, warm spaces, such as underneath a kamado; just like this yōkai. And they crawl out of the floorboards to scare those working late at night; just like this yōkai.

Himamushi nyūdō’s name contains a number of puns. According to Toriyama Sekien, it was originally called himamushiyo nyūdō (“monks who waste time at night”). Over the years, the pronunciation gradually morphed, and it became associated with hemamusho nyūdō—a popular Edo period word doodle in which a monk is drawn using the characters in its name: ヘマムショ入道. The connection with this cartoon character would probably have amused readers during Sekien’s time.

APPEARANCE: Ōmukade are monstrous mukade–centipedes (Scolopendra subspinipes) with dark bodies and bright orange legs and heads. They are often depicted with dragon-like features. While their non-monstrous cousins can grow up to 20 cm in length, the upper size limit on yōkai mukade is not known.

BEHAVIOR: Like their smaller relatives, ōmukade are vicious and highly aggressive. The bite of a regular mukade is venomous and very painful, but rarely fatal. Ōmukade, on the other hand, are much more venomous and very strong. They have even been known to torment dragons.

An ōmukade’s exoskeleton is so tough that it can’t be pierced by weapons. They do have one weakness though: human saliva is toxic to them. A weapon coated in saliva may be able to pierce through its armor and wound it.

INTERACTIONS: Ōmukade are extremely rare. When they are seen, they pose a threat to all in the area. Throughout history, the responsibility of exterminating these monsters has fallen on the shoulders of brave warriors.

LEGENDS: There is a famous bridge in Shiga Prefecture known as Seta no Karahashi. Long ago, a great serpent appeared on the bridge and would not move. The villagers were too afraid to approach the serpent, and so they could not cross.

One day, the brave warrior Fujiwara no Hidesato came to the bridge. He was not afraid of the serpent, and he crossed the bridge, crunching its great body under his feet. The serpent slithered back into the lake, and the bridge was clear again.

That night, a beautiful woman visited Hidesato. She introduced herself as the daughter of the dragon king of Like Biwa. The dragon king had sent her to Hidesato to ask for his help. Her family was being tormented by an ōmukade who lived on Mount Mikami. She knew that Hidesato must be a brave warrior, because he had so fearlessly trampled her body. Hidesato agreed to help the dragon king. He took up his sword and his bow and headed to the mountains.

Upon reaching Mount Mikami, Hidesato saw an enormous centipede coiled around its top. Its was so long that its body wrapped around the mountain seven and a half times. He fired his arrows at it until only one arrow remained, but he was unable to pierce the beast’s armor. Hidesato coated the tip of the arrow in his saliva, and said a prayer to Hachiman, the god of warriors. This time his arrow struck true, and he brought down the ōmukade.

The dragon king’s daughter was so grateful to Fujiwara no Hidesato that she gave him marvelous gifts: a bag of rice which never became empty no matter how much rice was taken from it; a roll of silk which never ran out no matter how much was cut from it; a cooking pot which always produced the most delicious food without the need for fire; and a large temple bell, which Hidesato donated to Mii-dera. The grateful dragon king also told Hidesato the secret to defeating Taira no Masakado, the rebel whom Hidesato had been charged with bringing down.

APPEARANCE: Haimushi is a tiny moth-like creature with a segmented body and four wings. They live in the lungs most of the time, but occasionally leave the body and fly through the air. They have red faces with a triple-forked mouth, and white bodies like that of a maggot. They have colorful, feathery wings. They feed mainly on cooked rice.

INTERACTIONS: Haimushi infect the lungs and cause various health problems. If a haimushi leaves its host and gets lost, the person will die and the haimushi will transform into a fireball and burn up.

A haimushi infection can be treated with byakujutsu, a traditional remedy made from the powdered root of the herb Atractylodes japonica.

TRANSLATION: the three corpses; the three spirits
HABITAT: inside the human body
DIET: unknown

APPEARANCE: The sanshi are three spiritual worms found inside of humans. Each is about 6 centimeters long. These worms live in their hosts from the moment they are born to the moment they die. They work hard to cause their hosts to do evil things.

INTERACTIONS: The names of the sanshi are Jōshi, Chūshi, and Geshi, meaning upper worm, middle worm, and lower worm.

Jōshi lives in your head and looks like a Taoist wise man. He is responsible for making your eyes grow weak, creating wrinkles, and growing white hairs. Chūshi lives in your torso and looks like a wild beast. He is responsible for damaging internal organs, making you overeat and overdrink, and causing bad dreams. Geshi lives in the lower half of your body and looks like a human foot with a cow’s head. He drains the will and shortens the life of his host.

The number 60 is an important number in Chinese astrology, and every sixty days the sanshi leave the body to visit the King of Heaven while their host human sleeps. They report their host’s wicked deeds for the year to king. Depending on this report, the King of Heaven shortens each human’s life span by a certain amount.

To escape the King of Heaven’s sentence, Kōshin practitioners do not sleep every 60th night, so the sanshi are never able to leave the body and give their report. Additionally, spells and charms are chanted to prevent any harm done by the sanshi. The following spell is said to defeat the sanshi’s power:

ホウコウシ、ホウジョウシ メイコシ シツニュウヨウメイイチュウ キョリガシン

Finally, if you find yourself drowsy and unable to stay awake, the following spell must be chanted before falling asleep to prevent harm:

APPEARANCE: Kamikiri are a kind of magical arthropod, with a scissor-like beak and hands like razors. They are small, and capable of sneaking quietly through open windows and doors without alerting their victims.

BEHAVIOR: A kamikiri’s modus operandi is simple: sneaking about at night and cutting a persons hair off suddenly and unexpectedly. They hide under roof tiles and wait for unsuspecting prey to pass by. They are indiscriminate in their attacks, going after men and women, servants and aristocrats alike. They strike in urban areas, particularly in alleys, or bathrooms, or other out-of-the-way places. In many cases, the incident goes completely unnoticed until much later, when the victim is spotted by a friend or family, or when a mop of cut hair is noticed lying in the street. Often the victim is asleep in bed when it happens. In the days when long hair was the only fashion in Japan, the kamikiri was a terrifying apparition indeed – particularly in high-class, urban areas. These days, such spirits are no longer feared as they once were.

Kamikiri attacks are sometimes a sign that the victim is about to unknowingly marry a ghost or a yokai. While these couplings are uncommon, there are a number of stories of kitsune and other shape-changers tricking unsuspecting men into marrying them. Because these improper marriages often end in catastrophe, kamikiri interfere in hopes that the wedding will be called off.

LEGENDS: One account of a kamikiri attack was printed in a newspaper as follows: On May 20th, 1874, in a neighborhood of Tokyo, at about 9 pm, a servant girl named Gin left her masters mansion to use the outhouse. She suddenly felt a ghostly chill, and a moment later her hair fell disheveled about her face as her long ponytail was lopped off at the base. Gin panicked, and rushed to a neighbors house where she promptly fainted. The neighbors investigated the outhouse, and discovered Gins severed hair strewn about the floor. Afterwards, Gin became sick from stress and returned to live with her family in the countryside. Nobody ever used that outhouse again.

APPEARANCE: The shōkera is a very large, dark-skinned, three-toed demon which spends most of its time lurking about on rooftops. Not much is known about this fearsome beast aside from its hunting practices, though it is believed to be some kind of demon with connections to Kōshin, an esoteric Japanese folk religion with origins in Taoism.

INTERACTIONS: Shōkera only appear on Kōshin-machi, a special night in the Kōshin faith which occurs every sixty nights. A shōkera spies through windows, doorways, or skylights in houses, watching for the inhabitants to do wrong or impious things, after which it pounces down in a vicious attack. Because Kōshin is no longer a very widespread religion, and because victims of shōkera attacks would only be implicating themselves as wicked by admitting to seeing one, little else is known about the shōkera’s specific mannerisms.

ORIGIN: According to Kōshin, there are three spiritual worms or insects, called the sanshi, which live inside every human body. Every sixty nights, on a special night called Kōshin-machi, these worms leave the body while their host human sleeps. The sanshi travel to Heaven to report on the good and bad deeds of their human. The emperor of Heaven then uses this information to lengthen or shorten people’s lives according to their deeds. While good people have nothing to fear from Kōshin-machi, the wicked might try to circumvent having their bad deeds reported by staying awake and reciting prayers all night long during these special nights so that the sanshi cannot leave the body. The shōkera lurks about on rooftops during these nights, peering into windows and hunting for anyone violating the laws of heaven in this way.